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3D objects
An object is something that appears in a 3D scene. All objects have transforms that define their location, rotation, and scale in a 3D space. You will find several types of objects in a 3D scene:
- Mesh: A mesh is the most common type of object in 3D; nearly everything we make is a mesh. Meshes are 3D objects that are made up of components (sometimes referred to as the geometry of the mesh). These components are used to form geometric polygons. Polygons are the multi-sided shapes that form the visible surface of a model. Creating 3D models with this approach is called polygonal modeling.
- Empty: An empty is an object that doesn't have any components attached to it. Some software packages call these null objects or locators. These are useful in advanced workflows for defining and keeping track of an exact spot in a 3D space. Since an empty has transforms, it will be present in the 3D scene just like all other objects, but because it has no components, it will not be visible in the final result.
- Light: A light is a type of object that casts light onto the scene. Just like in the real world, you can't see without a light source. If a 3D scene had no light source, you would just see black. Most 3D software includes a light source in the scene by default so that you can see what you're doing. Often, these default lights are a type of environmental light or ambient light source that illuminates the scene without necessarily coming from a particular point in the scene.
- Camera: A camera is a tool that's used to create the final image from our 3D scene. We can use a 3D camera the same way we would use a camera in real life: position it, aim it at the subject, and take a picture. The picture we take with a 3D camera is called a render. Rendering creates a high-quality image of the scene. High-quality renders take much longer to process than the normal Viewport preview of the scene, so we don't usually render until we are finished creating the scene.
Now that we know what an object is, let's take a closer look at the most important type of object: a mesh. We need to understand how the components of a mesh come together to create a 3D model.